Hows it everyone? I am trying to find some answers to a couple of question:

1-Is there a separate Fuel Pump Relay in the engine compartment other than the big one that mounts above the radiator with multi. wires going in it?

2-Is there a picture (schematic) available?

I had this same problem and it was a bad ground--do you think it may need repairing again?
I use to hear the pump pick up and now it doesn't. No fuel come from fuel rail. Pumps not a pumping.

Are their fuses (where and which one is for the pump) Already checked the rear end collision device and is in the close position.

Any suggestions and I will surely appreciate it.

Thanks!!!

 

Welcome to the site..

The fuel pump relay is internal to the constant control relay module (CCRM).. There's a 20amp fuse in position #10 in the engine compartment box for the pump.. Couple checks you can make if you have a 12v test light,,

1. First check the fuse in the panel for voltage (both sides), if OK, then check for 12v (hot at all times) on the 'Orange' wire going into the CCRM connector.. That is the power IN to the fuel pump relay (switched side) in the CCRM and from the fuse box..

2. Have someone cycle the key to 'ON' with a test light on/probing the LB/O wire, and again cycle the key and check for voltage on the DG/Y wire.. The LB/O wire is voltage IN to the relay's magnetic coil for PCM control (will be timed if a no start) of the fuel relays contacts, and the DG/Y wire is voltage OUT of the relay and into the inertia (if the relay closes) if a voltage IN to the relay is present from the PCM, and a good ground..

3. If you cycle the key ON and you have voltage on all 3 wires (again, the LB/O and DG/Y will be timed ON) then the relay is working.. Then go to the inertia switch and check 'both' wires IN/OUT of the switch.. Be sure the fuse is good, and if so, that there is voltage on the orange wire to the CCRM.. The chassis ground is out by the battery/inner fender..

 

Thanks SuperMod & thanks for the welcome---I'll check all the above and let you know what I find!

Thanks!

 

I put the incorrect year--My car is a 1994 Taurus GL / 3.8L that was built on 10/93. Sorry for the mistake--My eye's are not what they use to be..I noticed the color of the wires are different and that the engine compartment fuse box had no 20amp. fuses--The smallest being a 30amp..I cleaned all my gronds check voltage coming & leaving the fuse Box in the engine and inside the car drivers side today and was unable to check the power leaving the relay due to the color diffeerence's. Can I use a Fluke meter (volt meter DC) and look for 12VDC in place of the test light correct? Any help at this time would be greatly appreciated.

Also, I had this problem a little over a year ago and found the ground was not malking causing my pump not to run. On this occurance when I went to start the car I heard the pump and the car went to start then died.---Thanks for the froum and the help[!!

 

Power into the CCRM for the fuel pump relay coil will be a 'Yellow' wire..The power 'out' of the relay if it's good and closes is a PK/BL wire on out to the inertia. I made a mistake also and the LB/O is actually the 'ground' for the fuel relay and is PCM control of the relay coil to close the contacts.. The fuse in the engine compartment box #3 position 30 amp is for the PCM/Fuel relay.. If you have voltage out of the PK/BL at the CCRM and in/out of the inertia, have someone cycle the key ON or crank the engine and give the bottom of the fuel tank a 'hardy' thump.. Sometimes the pump will start if it's go'n south, sometimes they just die.. DVOM will work fine..

 

Like always thanks again for your help--will check . One more question ,"Is it O K to spray a little starting fluid into the Air Filter and if it runs a bit , that tells me it is the pump? Don't know how this would tell me everything else is working ok. Did not make sense to me but thought I'd ask.. Will it hurt anyrthing?

 

A light shot of fluid to assist start isn't going to hurt, but it would only prove that the ignition fires and base engine is OK. Could still be an issue with the fuel injection or no fuel drop if just adding a combustable to the intake.. In your original post you said 'Pumps not a pumping' and if so, verifing the pump run and a good fuel pressure/volume at the fuel rail would be a good bet.. If someone cycle's the key ON, and you listen at the tank or in the open fill neck, do you hear the pump run? Voltage checked through the inertia switch?

 

O K I checked in/out relay for pump---11VDC, In out anertia-11 VDC also. Can't hear the fuel pump and a slight shot of starting fluyid started the car for a minute. I put it on charge and will see if that makes the difference in the missing 1 or 2 VDC. I am unable to hit the tank as the car sits a bot low but will try my best. If not looks like a trip to my buds on Thursday to replace the pump.

If the pump starts again after I try it again today do you recommend still replacing. I,E.,maybe it got stuck--something like that?

Thanks again for your help Hayapower--What do you think a pump will cost?

 

Hayapower----Just wondering why you can't check the voltage from the inertia switch only--Is that how the circuit runs? From the relay to the inertia switch in series? What I'm thinking if this is the case as long as you have VDC leaving the inertia switch then the pump is getting power also---This is bringing out the electrical theory in me I guess----I appreciate all your help---Got Pump and will be installing later this evening....

 

Thats exactly how the circuit is supplied..

You can check just off the inertia, or even down on the fuel pump module connector to be certain the circuit is complete 'and' active. It's easier at times to work your way backwards (actually upwards to diagnose a power distribution problem and/or rule out failed components..

If you cycle the key ON (indicated voltage will be a bit lower because of the total system draw in a no run condition) and you have voltage at the inertia both sides (remember it's timed) chances are there's voltage to the pump, but not a bad idea to check at the module connector prior to a pump replacement..

As far as the fuel relay,,, the PCM controls the the fuel pump relay ground, and battery voltage is at one side of the relays open contacts if the fuse is good.. Key ON, voltage is now/added to the relay magnetic coil and only needs the ground to be supplied to close the relays contacts.. Once the contacts close,, voltage runs through the closed contacts and on out and through the inertia, finally down to the pump..

If there was no voltage at the inertia, and the fuel pump circuit fuses all proved out OK with voltage on both sides, then looking at the CCRM for power in/out of the relay would be a good bet..